NorthStar Navigation Multi-Function Unit M84 - Manual (Page 96)

Northstar M121/M84 Installation and Operation Manual 95
20-5 Installation: GPS antenna
Selecting an antenna
Fit one of these GPS antennas:
• Normally use the GPS antenna supplied.
• An optional differential beacon DGPS
antenna to give enhanced accuracy within
range of land based differential beacons
in areas where WAAS or EGNOS are not
available. Such a DGPS antenna has both a
GPS receiver and a beacon receiver, and it
automatically applies the beacon correction
to the GPS position.
• A compatible GPS or DGPS instrument or
antenna connected by NavBus (see section
20-10) or NMEA (see section 20-11). In this
case, the Instrument does not need its own
antenna.
Note:
• To configure the Instrument for different
antenna options, see section 19-4.
For more information, contact your Northstar
dealer.
DGPS Source:
Enables or disables the satellite based DGPS
correction (see section 8). The options are
None or WAAS/EGNOS. Do not Enable
WAAS/EGNOS outside their coverage areas
or the accuracy of the position might be
degraded.
! WARNING
MOB will not work if the Instrument does
not have a GPS fix.
WAAS covers all of the USA and most of Canada.
To use WAAS, the GPS antenna must have
a clear view of the sky towards the equator.
EGNOS will cover most of Western Europe.
Restart GPS:
Restarts the GPS receiver, satellite reception will
be lost until the receiver completes its restart
and acquires the satellites.
Select restart GPS and press
ENTER
Installing an antenna
If an external antenna is required, install the
antenna and fit the antenna cable back to
the display unit. Follow the instructions in
the manual supplied with the antenna. Fit an
optional Northstar extension cable if required.
During setup, configure the Instrument for the
chosen antenna, see section 19-4.